Ilocos is located in the north-western part of Luzon, with the South China Sea to the west and the Cordillera, the highest mountain chain in the country, to the east. The region is composed of four provinces: Ilocos Norte, Ilocos Sur, La Union, and Pangasinan.

Cool almost all year round, it is usually wet in August and dry from October to May. January and February are the coolest months.